Process of bleaching sugar.



FTCE.

MANUEL BARRIOS, OF HABANA, CUBA.

PROCESS OF BLEACHING SUGAR.

No Drawing.

To all whom it may concern Be it known that I, MANUEL BARRIOS, citizen of the Republic of Mexico, residing at the city of Habana, Cuba, temporarily,

have invented new and useful Improve ments in Processes of Bleaching Raw Sugars, of which the following is a specification.

This invention relates to the process of bleaching or by submitting the same to a bath of glycerin saturated with sulfurous acid, and afterward bleaching said sugar by mechanical means, utilizing adequate clothsor woven fabrics. v

The process consists in bleaching the raw sugar, or sugar of a low polarization in cold, and without the need of dissolving it, by treating it with glycerin saturated with sulfurous acid and in quantity necessary for this substance to coat all the sugar crystals. Then by suitable and well known mechanical means and employing adequate woven fabrics or cloths, to separate the glycerin whichwill carry oif in solution all foreign and coloring matter which enveloped the sugar crystals, the latter then remaining white and perfectly pure.

The processes employed up to the present time in sugar refineries in general, consist in dissolving raw sugar in water, and then afterward treating these solutions by different chemical reagents to purify and decolorize them. All the efforts tending to the improvement of this process have hitherto consisted in varying the chemical reagents to purify and decolorize, but always upon the basis of the dissolution of the sugar in water, and no one previously, so far as I am aware, has attempted to refine raw sugars in cold and in a solid condition The improved process in detail is as follows: In a tank with blades such as is used in the sugar factories to cool off the boiled mixtures, the raw sugar and the glycerin mixed with the sulfurous acid, or other decoloring substance that may be chosen, are all mixed together in a sufficient quantity to bathe or cover the crystals of the sugar. The quantity of glycerin mixed with de- Specification of Letters Patent.

Application filed May 2, 1912. Serial No. 694,642.

whitening raw sugar, in cold,

coloring matters varies from 4% to 6% of the weight of the sugar. After obtaining a perfect mixture with the sugar and glycerin, it is placed in a common centrifugal machine, which should be covered internally with a heavy linen cloth, such as that called crude holland, and by these means it is cleaned. If after this purge the sugar is still somewhat yellowish, the mixing with. glycerin and the purge are to be repeated in the manner above indicated. After cleaning the sugar thus, there are several ways to eliminate the insignificant glycerin attached to the sugar crystals. Two out of these several systems will be described: One, and the quickest, although it causes some loss, consists in the application of a little clean water when the sugar is still in the centrifugal machine and right after the operation of purging, the water carries out the remainder of the glycerin absorbed by the linen cloth covering the inside of the centrifugal machine; the other system consists in passing the sugar, after the purging operation is done, from the turbine to a drying machine, also supplied with internal cloths, just as it is done in the sugar refineries, the above mentioned cloths gather up the glycerin by the constant friction of the sugar crystals against the cloth covered walls of the drying machine. This'form is slower, but there is no loss in it.

I therefore claim as my invention, the following The herein described process of treating sugar, which consists in treating it at ordinary working temperature with a mixture of glycerin and sulfurous acid, whereby the impurities will be dissolved and then separating said mixture containing the said dissolved impurities from the sugar crystals.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

MANUEL BARRIOS.

Witnesses:

ALFREDO on NORIEGA, C. STEWART ONEJLL.

Copies of this patent may' be obtained for five cents each, by addressing the "Commissioner of Patents,

Washington, D. G.

Patented Nov. 17, 1914. 

